Comparative slope analysis by methods of slices and finite element analysis

Slope stability studies are conducted to provide an economical and safe design of embankment, landfill and excavation. There are basically two main methods namely LEM (Limit Equilibrium Method) and FEM (Finite Element Method) which can be used to analyze slope stability problems in real life. The conventional LEM which includes Ordinary Method of Slice, Bishop’s Simplified Method and Spencer Method is commonly used in geotechnical engineering when calculating FOS (Factor of Safety) in slope analysis. As technology gets more sophisticated, more advanced finite element soil analyzing programs were introduced and slowly gaining popularity in geotechnical field over the past decades. Different computer programs such as Slide 6.0, Phase2 8.0 and Plaxis 2D are used to determine FOS in different slope stability problems. Slide 6.0 is the LE (Limit Equilibrium) based computer program while Phase2 8.0 and Plaxis 2D are the FE (Finite Element) based computer programs. Comparative analysis between both LEM and FEM are performed for the selected hypothetical and real case studies. Meanwhile, assumptions which cause the differemce in output from different methods and different computer programs are also identified. All the computer programs used show a clearer picture of how the input parameter affects the output. Provided appropriate settings are chosen, most of the results generated from all the computer programs agree within acceptable limit. Slope stabilization techniques play a very significant part in the analysis because they can be executed as preventive measures at early design stage or as remedial measures after occurrence of slope failure. Selection of slope stabilization measures greatly depends on the soil conditions at site.Bachelor of Engineering (Civil